Player profile: Is Chelsea's latest signing Nemanja Matic really worth £21m?

Chelsea have completed the purchase of Nemanja Matic from Benfica, for a fee of £20.75m, three years after selling him in the opposite direction.

The Serbia midfielder signed a five-and-a-half-year deal and will have a crucial role as Chelsea try to secure their first Premier League title since 2009-10.

While many say that Jose Mourinho’s squad most obviously lacks centre-forwards, their lack of quality in front of the back four is at least as much of a problem. The arrival of Matic, vastly improved as a player in his two and a half years in Portugal, should help with that.

During Matic’s first spell at Chelsea – he arrived from MFK Kosice soon after his 21st birthday – he made just three substitute appearances and clearly did not feature highly in Carlo Ancelotti’s plans. Matic was loaned out to Vitesse Arnhem in the Netherlands, then used as a makeweight in the deal to bring David Luiz from Benfica, along with £20m.

Matic improved so much during his time in Portugal that he now justifies his big-money price tag, and is certain to improve Chelsea’s midfield. When Matic arrived at Benfica, he was used to playing in central or even attacking midfield, and generally sat on the bench behind Javi Garcia.

But in the summer of 2012 Benfica sold Garcia to Manchester City and then Axel Witsel to Zenit St Petersburg, and needed a new defensive midfielder. Matic was drafted into the role and instantly showed his class, helping Benfica to forget about Garcia quickly.

Last season was Matic’s true breakthrough year, as he helped Benfica to a painful second-place league finish, one point behind Porto; the final of the Europa League, which they lost to Chelsea in stoppage time; and the semi-finals of the Portuguese cup. Despite winning no trophies, Matic took the Portuguese player of the year prize.

Close observers of Matic in Portugal speak very warmly of his performances, saying that the €25m fee is cheap for a player who could have been sold for €35m or more.

One Portuguese reporter described Matic as “like Essien with skills” and there is certainly a confidence that he will improve Chelsea’s midfield options.

Frank Lampard is not as sharp as he used to be while Jon Obi Mikel has had a quiet season, and some authority and class in central midfield is just what Chelsea need. Ramires is the first choice there but he is often moved wide into a 4-3-3 system for difficult away games, a process Matic would help with.

Mourinho, who has not worked with Matic before, said he was delighted to have the much-improved player in his squad for the second half of the season. “I am very pleased that Nemanja is returning to Chelsea,” he said. “He has grown as a player in Portugal and has become a fantastic all-round midfielder. I am sure he will become a very important member of the squad and help us to achieve our ambitions.”

Matic was also pleased to be back at Chelsea, where he will be eligible for Premier League and FA Cup games this season but not for the Champions League due to his participation in the European competition with Benfica.

“I am very happy for this opportunity to be back at this club,” he said. “I feel very good because of that and just want to say I will give my best to help the team and make the Chelsea fans happy.”